Fixing A Cub Cadet 4 Cycle Trimmer That Won't Start

[@hickorystx]

It did start even with low compression so that gave me the energy to continue on. One less item for the trash!!! It lives on...thanks to you and your persistance. 😀

[@INSIDEHOUSEGARAGE]

I know right, If I get this machine back, I'll try to do the compression test again, just to make sure

[@aleblanc3547]

I have a Honda 4 cycle and aside from being a little heavier than a 2 cycle it is perfect. 22 years old and still starts on the second pull. Thx bud!

[@INSIDEHOUSEGARAGE]

wow nice!

[@robertmailhos8159]

Your co workers are definitely keeping you busy 😂

[@INSIDEHOUSEGARAGE]

I know right!

[@robertmailhos8159]

@@INSIDEHOUSEGARAGE yeah buddy 😎😁

[@motorizedandrew3942]

If it runs and starts good obviously the engine could care less about low comp. Something to keep in mind is on a lot of those engines they had comp reliefs built into the cam. They were a pawl like the starter pawls but spring loaded and attached to flyweights. As you started the engine these Pawls would engage with the litters to hold down the intake a little longer to make starting easier. Like I said it’s not too uncommon. Oh also when you go to adjust valves you can make it easier on yourself by finding the comp stroke. Both valves will be closed and thus not under any load. It just makes it easier and you don’t have to turn the engine over more than once

[@INSIDEHOUSEGARAGE]

yes, I might have used the drill in 1st gear instead of 2nd and that might be the reason why the compression was low. The relief was still in play.

[@karlschwab6437]

I have a trash picked Husqvarna 125e lawn edger that is complete, has 60 psi compression and will not run. Piston and cylinder looks good. I cleaned it all up, will reassemble and then do a vacuum and pressure test of the crankcase. Spark is ok, carb will go through if engine will pop off. Just doing all of this for fun.

[@INSIDEHOUSEGARAGE]

I like your perspective on the project

[@cedriclynch]

I once repaired a chainsaw that would not run although it had good compression and spark. The problem was that the flywheel key was broken and the flywheel had slipped round on the shaft so that the spark was not occurring at the correct time.

[@MarkMeadows90]

Answering your question, if it was for a customer, I would continue the repair and let the customer know of the low compression issue. It still works, and I'm sure it'll work for some more years of service.

[@INSIDEHOUSEGARAGE]

I totally agree

[@jesterr7133]

I had a pretty good score yesterday. My neighbor found two mowers in the trash and brought them to me. One was just a cheap small Murray, and the other was a Craftsman Gold Series self propelled with a Briggs 6.25 engine. I now see why you spend so much time cleaning the underside of the deck. Someone had thrown the self propelled mower in the trash. When I pulled on it, the engine wouldn't turn, so I reached under and tried to turn the blade by hand. Guess what the problem was. There was so much hardened grass caked on the underside of the deck that it was actually preventing the blade from turning. I cleaned the underside of the deck, put some gas in it, pulled on it a few times, and it fired right up and ran great. It needs a quick carb clean and a thorough cleaning throughout, but other than that, there is nothing wrong with it. Someone junked a nearly new self propelled mower simply because they never cleaned it, lol. I got a really nice free mower. I'm going to do a full service and put a blade on it for S's and G's. The little Murray mower just needs a carb clean and service, so I scored on this one.

[@INSIDEHOUSEGARAGE]

wow you did score! Congratulations!

[@pit4955]

Gas trimmer, gas chain saw, gas blower = gas/oil mixture. How many do you think would automatically put this mixture into fuel tank 🤔 Most likely I would have stopped once knowing that low of compression, but again I have ran similar equipment with low compression until it died. Thx for great troubleshooting vid👍

[@INSIDEHOUSEGARAGE]

thank you for your comment and your time

[@venturinix]

Ciao bel video che cilindrata ha questo decespugliatore?

[@INSIDEHOUSEGARAGE]

ciao, sono 25 cc.

[@josephmeadows8521]

Amazing video, if my compression gets low on my weed eater than I can buy a new block😊

[@INSIDEHOUSEGARAGE]

yes you can, but to be honest, I'd just find another used machine and hope that engine is not worn out. The price of a new short block is quite high.

[@jjjuarez312]

Good Job Man.. keep the videos coming

[@INSIDEHOUSEGARAGE]

I will, thank you!

[@Kyle-bb9zp]

My grandfather bought a Ryobi one 4 cycle i thought was wired. It doesn't run but i tryed to get it running haven't yet. I think I will be taking the carburator a part carfully and slit cleaning tgen i think it will run also have to replace the fuel lines on it as well.

[@INSIDEHOUSEGARAGE]

good luck to you the project then

[@larryz24]

What is the soaking solution that you use? It looked like motor oil. Thanks.

[@RussellBooth1977]

I think that he uses brake fluid !

[@INSIDEHOUSEGARAGE]

yes I use brake fluid.

[@INSIDEHOUSEGARAGE]

Thank you Russell Booth

[@innerman7096]

The soaking solution looks like brake fluid

[@INSIDEHOUSEGARAGE]

you are correct

[@NickSpires09]

Great video but I have a question to you have change the oil in this or do you mix the fuel and oil ?

[@INSIDEHOUSEGARAGE]

you have to change the oil , no mixing here.

[@NickSpires09]

@@INSIDEHOUSEGARAGE thanks

[@cedriclynch]

May I suggest that the low compression was caused by the amount of space inside the adaptor that you had to use because the spark plug thread is of a smaller diameter than the thread of your compression gauge? This space must be quite large by comparison with the cylinder head volume of the very small engine.

[@INSIDEHOUSEGARAGE]

unfortunately I don't see it that way. Instead, I think I was using the drill in 1st gear, which wasn't allowing me to bypass the compression release. If I had done it in 2nd gear, I think the reading would have been twice that amount. Of all the compression testers I've used, none of them have been stated for "small engine use" and they've worked great on both cars and trimmers.

[@RussellBooth1977]

I think that the engine still wasn't spinning fast enough to disengage the compression release mechanism & if it's not burning oil like my dads Honda GX35 engine was on his brush cutter then I would be worried that the engine is worn out, it could've also been carboned up valves or even sticking piston rings which caused the engine to have low compression. I am wasn't sure why you needed to use a small D driver to adjust that mixture adjustment screw because it looks to be the same as the Walbro WYL (4 stroke) carburettor which requires a small 2.5 millimetre flat bladed jewellers type of screwdriver to adjust. Some of them require the small D tool to adjust it. All of the Honda GX35 & GX25 engines use the same carburettor !

[@INSIDEHOUSEGARAGE]

you might be right, I may have had the drill in 1st gear instead of 2nd.

[@CTrickle241]

What solutions did you use to: 1) Clean the housing with such great results? 2) Soak the diaphragms in?

[@INSIDEHOUSEGARAGE]

1. I use Super Heavy Duty Degreaser from Harbor Freight 2. I use brake fluid

[@lewiemcneely9143]

Kept going. I'm bullheaded.

[@INSIDEHOUSEGARAGE]

nothing wrong with that

[@lewiemcneely9143]

@@INSIDEHOUSEGARAGE My old c.b. handle my kids laid on me was 'HAMMERHEAD'.

[@josephmeadows8521]

Surprisingly for my weed eater, it actually costs $30 which is crazy cheap for a Husqvarna

[@INSIDEHOUSEGARAGE]

thats a great price

[@jesterr7133]

Are you sure that engine doesn't have a compression release? Sixty PSI would be the expected reading if it did. I am about to tear into my first 4 cycle weedeater, so I am just curious.

[@INSIDEHOUSEGARAGE]

I think my problem was that I was in 1st gear with the drill which wasn't enough RPMS to overcome the compression release. IF I had to guess, the engine's compression is closer to 120 PSI.

[@jesterr7133]

@@INSIDEHOUSEGARAGE I thought that had to be the case since it started so easily.

[@Seth_Lekas]

I’ve got an engine that I just rebuilt the carb on. Fuel will get to the bulb, but no fuel in going to the cylinders. Do you have any idea why that is?

[@INSIDEHOUSEGARAGE]

sure, did you confirm that fuel was flowing thru the inlet screen before reassembly? Also did you replace the metering diaphragm with the same type as was in it? If it was me, I would just replace the carb, that way you use your time wisely. I've spent a lot of time on stuff before finally just replacing the carb.

[@Seth_Lekas]

I just went ahead and bought a new one. Even after rebuilding it fuel was still dumping out of the front of the carb

[@24BLUEELMO]

Low compression is because of decompression mechanism to make the trimmer easy to start . Most 4 cycle engines have them

[@INSIDEHOUSEGARAGE]

agreed, although if I had used 2nd gear on my drill instead of 1st, I think I would have gotten a better reading, probably at least double from my initial reading. It was my fault for not realizing it during the test.

[@garyhockensmith2471]

On your compression I have found that using the adaptor that does not have a valve In it will lose half of the compression in that small of an engine and I can never get a good reading over 50 psi! Purchased an adapter with a one way valve and my compression jumps to over 100 psi

[@INSIDEHOUSEGARAGE]

thanks for the information

[@christophermarshall5765]

I would have continued with the repair. It might have a decompression system for easy starting.

[@INSIDEHOUSEGARAGE]

yes, I'm pretty certain I only had the drill on 1st gear, which wasn't enough RPMs to overcome the compression release.

[@MazichMusic]

I'm assuming this is a sister product of the Troy Bilt 4-cycle trimmer....

[@MUUKOW3]

Same Chinese trimmer just a different color.

[@INSIDEHOUSEGARAGE]

yes that's a safe assumption

[@joebrown9621]

It's a 4 stroke.. nahh they don't need a ton of compression 😅 probably as it's pure gas with a higher flash point it ran, sounded good no smoke.. that's a win 😁

[@INSIDEHOUSEGARAGE]

ah great point!

[@MRMONKIBONES]

I think, you may need a different compression tester for these to y engines, due to volume you are compressing

[@INSIDEHOUSEGARAGE]

it turns out I was not spinning the engine over fast enough to overcome the compression release. I should have put the drill in 2nd gear

[@beplh5242]

Being 4 cycle is probably has a compression release thats why you have low compression

[@INSIDEHOUSEGARAGE]

I think you're right

[@zakburnett6690]

I've never seen anything that small have a compression release

[@izaacsilva9148]

That’s just how those weed eaters are. They have a compression release no matter if you spend it with a drill or pull it by hand it’ll always show 5060 psi I know because I have a brand new one and I’ve tested the compression and it shows 50

[@INSIDEHOUSEGARAGE]

Yes I don't think I was spinning it fast enough to overcome the relief. That was my bad.

[@scottdunn4506]

You may not like 4 cycle weed whackers but they do have more power than 2 cycle weed whackers only my opinion also 4 cycle weed whackers sound more powerful than 2 cycle weed whackers

[@INSIDEHOUSEGARAGE]

my main gripe it the weight. As the years run me over, I've gotten quite weak compared to when I was 20, but I think that's everyone

[@MUUKOW3]

They don't have more power but do have a better low end tourque and are much better at just part throttle running without carbon build up. The four cycles require more maintenance, oil changes,valve adjust and storage in the right position to keep the oil from leaking out.

[@joebrown9621]

​@@MUUKOW3 quite so they have a lot of low end torque virtually impossible to stall them plus they're nice for trim along a house or in line of sight of a window where a small amount of throttle is needed.. The Honda engine with over head cam didn't say anything about valve adjustment on those models.. one other bonus they're a lot more fuel efficient

[@MUUKOW3]

@@joebrown9621 The Honda with the overhead cam still requires a valve adjustment. They are great trimmers except for the weight . They are fuel misers and brush cutting monsters!

[@liljoeii6091]

I think if I can run why not use it thank you for the video

[@INSIDEHOUSEGARAGE]

I like your point of view

[@jbwright4]

Since you used a coupling on the compression tester hose, the reading you are getting reads low.

[@INSIDEHOUSEGARAGE]

really? always worked on the other stuff I use It on.

[@jbwright4]

If the Schrader valve remains at the same place and you use the compression tester with an adapter, you have effectively made the adapter part of the cylinder area. This makes the entire compression decrease.

[@philliphall5198]

How many videos do you make each day??

[@INSIDEHOUSEGARAGE]

it depend on the day of the week but I repair at least 3 to 4 machines a week, but I only produce 2 long from videos along with 4 shorts videos a week. The schedule might change, due to time tho.

[@zakburnett6690]

Just gas with no ethanol, if you ask a dealer you can buy that brand at they'll say run premium. Idk about your country but in Canada they don't use less ethanol they use more in premium so your really doing more damage putting premium gas in your small engines, just saying. Also you can find boat gas usually it's hard to find and expensive tho mostly it's just at boat docks, out west a seen a handful of gas stations that offered ethanol free gas it was all way more expensive than exen premium gas at the same place

[@INSIDEHOUSEGARAGE]

thank you for sharing that information

[@jesterr7133]

I hate to junk any machine that doesn't have a catastrophic failure, but this one had a ton of minor things wrong with it, and it probably wasn't worth messing with.

[@INSIDEHOUSEGARAGE]

it's actually a lot worse than I portray it in the video, so I agree with your assessment

[@MUUKOW3]

Those are not going to be anywhere near 100psi compression. 60 to 70 is about normal

[@INSIDEHOUSEGARAGE]

probably, I'll have to do more testing to find out .

[@don1857]

4 cycle was the worst thing to happen to portable outdoor equipment next to batteries. 2-cycle is simple, needs no crankcase oil and can be used in any position. Cheaper and simpler to repair as well.

[@joebrown9621]

😂 what are you talking about.. sure they have some draw backs.. if 4 strokes had more adoption possible less battery stuff would be on the market.. 4 strokes are way way easier to start one of the reasons people went to battery stuff plus can run on a bit staler, more fuel equipment has a wider torque band, the newer one's can run 90 of axis on either side.. use 50ml of oil for service, one quart bottle would last year.. would burn a lot more 2 cycle oil in that same period plus the higher quality engines last longer but cost more.. some stuff like 2 cycle lawn mower or generator can stay buried

[@INSIDEHOUSEGARAGE]

some would disagree, but I value your opinions. I like the simplicity of 2 stroke stuff too.

[@jwayne777]

Yeah that's 60 psi That's a no-go for me I probably would have just kept it for parts I honestly can't see it lasting more than a year of heavy use

[@INSIDEHOUSEGARAGE]

I know right!

[@briantii]

5 years old and destroyed. Insane. My oldest equipment is way older and looks 10 years newer than this.

[@INSIDEHOUSEGARAGE]

I know right!

[@Kyle-bb9zp]

Boy have to say i would think your co workers would take better care of there equipment because you would tell them how to do it right so you wouldn't have to work on it all the time.

[@INSIDEHOUSEGARAGE]

you can't make them do what you want them to, no matter how close you are to them.

[@Delerium22]

Honestly I don’t really understand the point of having a four cycle trimmer when you can just get a more powerful two stroke, but that’s just me though 🤷

[@INSIDEHOUSEGARAGE]

I know right!